Packing system for unit loads

ABSTRACT

The invention relates to a packing system for unit loads which can be stacked in a plurality of adjacent piles or piles stacked on top of each other to form a substantially stable pile consisting of at least two stacked layers of unit loads. The invention is characterized in that spacers are provided between at least two successive stacked layers so that both stacked layers are vertically interspaced; at least one device is provided on top of and below the stack to protect at least partially the external contour of the unit loads located in the top and lower stack position; at least one fixing device encompassing the other periphery of the stack is included so that it encompasses the stack in such a way that the unit loads in a stack position are pressed against the unit loads in a directly and vertically adjacent stack position; and the fixing device extends over the protection device.

Applicant hereby claims priority under 35 U.S.C. 119(a)-(d) based uponprior patent application Ser. No. 197 31 470.8, filed in Germany on Jul.22, 1997.

BACKGROUND OF THE INVENTION

The invention relates to a packing system for unit loads which can bestacked in a plurality of adjacent piles or piles stacked on top of eachother to form a substantially stable pile consisting of at least twostacked layers of unit loads.

The unit loads to be considered are plastic foam boards, used primarilyin the construction industry for cushioning or insulation. Typical sizesfor these boards for the construction sector are approximately 600 mmwide and approximately 1250 mm and 2500 mm long, due to the standarddimensions established in that sector. The boards are approximately 20to 200 mm thick, bundled together in packages of between 300 mm and 420mm in height (predominantly 400 mm). In the specification that follows,reference is made to these dimensions, which are customary in theconstruction sector, but without restricting the invention to thesedimensions.

After production, the packages of foam boards, packaged in shrink film,are bundled together in over-sized units and placed in storage.Deliveries to building materials merchants and construction sites aremade using large capacity trucks, with the packages resting on battensor directly on the loading surface (FIG. 1).

At the merchant's premises or the construction site, the products areusually unloaded manually, i.e. the entire load is removed from thecargo space separately package by package. The reasons for this manualunloading procedure are as follows:

While it is true that the packages may be atop battens, special stackerswith long prongs or fork attachments are rarely available. The blocks,which it would be possible to unload with long stacker prongs, are toolarge for internal materials handling. Their height (e.g. 3 m) precludesthe possibility of simply commissioning from these large units. In orderto remove the uppermost packages from such a block, a ladder or someother form of assistance is needed. The units, as delivered, cannotsimply be transferred onto the usual delivery vehicles, whose maximumloading height ranges from approximately 2 to 2.5 m.

The underlying task of the invention is to further refine a packingsystem for unit loads according to the preamble to claim 1 in such a waythat a minimal expenditure of effort for implementing all handlingprocedures involving the unit loads, from their manufacture to theirutilization at the construction site, should be made possible.

SUMMARY OF THE INVENTION

According to the invention, a packing system for unit loads according tothe preamble to the main claim is designed in such a way that spacersare provided between at least two successive stacked layers so that bothstacked layers are vertically interspaced; at least one device isprovided on top of and below the stack to protect at least partially theexternal contour of the unit loads located in the top and lower stackposition; at least one fixing device encompassing the outer periphery ofthe stack is included so that it encompasses the stack in such a waythat the unit loads in a stack position are pressed against the unitloads in a directly and vertically adjacent stack position; and thefixing device extends over the protection device. This method ofsecuring the stack, e.g. wooden laths on the top and bottom and anencircling band with high tensile strength, provides maximum protectionof the product and simultaneously a high degree of stability of theunit, because the horizontal forces of the encircling band are absorbed,at the top and the bottom respectively, by the wooden laths, and do notcause the two upper and lower packages to be pressed against each other.Loads on the package edges are likewise eliminated (FIG. 4). The entireunit is subjected only to vertical pressure, such as that in a press. Inaddition, the wooden boards serve to protect against wear and tear ontop of and underneath the unit. High pre-tensioning results in a highlystable loading unit; this guarantees, firstly, good handling propertiesand, secondly, that there is no relative shifting within the stack,resulting in a decreased risk of damage to the outside edges of theboards. Furthermore, this also creates a relatively unbroken outerprofile without protrusions, leading to a further reduction in the riskof damage from being subjected to partial pressures, including pressuresfrom outside. The invention is described in greater detail withreference to the figures below. They show:

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

FIG. 1: Examples of loading unit construction and cargo space in a largecapacity truck

FIG. 2: Stack formation after production

FIG. 3: Method of securing stack

FIG. 4: Existing forces within the stack and mechanical properties

FIG. 5: Alternative versions for intermediate layers

FIG. 6: Bundling stacks together

FIG. 7: Storage of blocks

FIG. 8: Commissioning procedures

FIG. 9: Loading at manufacturing site

FIG. 10: Arrangement in cargo space

FIG. 11: Unloading at merchant's premises

FIG. 12: Storage at building materials merchant

FIG. 13: Commissioning procedures at premises of building materialsmerchant

FIG. 14: Loading at premises of building materials merchant andarrangement in cargo space at time of shipping

FIG. 15: Unloading at construction site

DETAILED DESCRIPTION OF THE INVENTION

The packages of boards are first made into stacks, where plastic foambattens are inserted after the first two to three layers to separate thelayers (FIG. 2). Then, wooden laths are added on top of and beneath thestack, the stack is encircled with a band and, where appropriate,adhesive strips are affixed to the sides facing outward (FIG. 3). Theadhesive strips affixed to the sides can serve to hold together the toptwo package stacks when the encircling band is severed. Given 1.256 mboards, the size of this stack is approximately 1.25×1.2×2.9 m (L×W×H).The wooden laths may also have an indentation for the encircling band.

Different options can be used to separate the upper and lower partialstacks (FIG. 5).

1. Foam battens on the upper stack portion, fastened or not,

2. No-return pallets with top and bottom liners made of corrugatedcardboard and polystyrene foam battens, and

3. Foam battens made of several layers of polystyrene foam, wherein thethickness of each individual layer is the same as that of thecorresponding boards, allowing these materials to be possibly re-used onthe construction site.

The stacks are then bundled together into a block of four (1.25 mboards) or block of two (2.5 m boards) (FIG. 6) and a means of securingthe loading unit is applied (e.g. a wrapper made of stretch film or topand bottom boards). The blocks thus formed are then stacked for storage(FIG. 7).

Individual stacks can then be placed together with different products(FIG. 8) for commissioning. In the case of smaller customer commissions,the individual stacks can also be broken up and, where appropriate, putback together again. It is then possible for the most widely varyingunit sizes to be loaded at the manufacturing site (FIG. 9), whereby itis possible to load not only the large units, but individual stacks oreven partial stacks (e.g. 4 or 10 packages) as well, using forklifts todo so. The “jumbo” cargo space may then contain large units of 2.4×2.5m, individual stacks, partial stacks, or individual packages (FIG. 10).On the premises of the building materials merchant, variouspossibilities exist for unloading the truck (FIG. 11):

1. If long fork attachments are available, large blocks that are 2.4 mdeep can be unloaded (it must however be possible to drive in at auniform height).

2. Individual stacks that are 1.2 m deep can be unloaded using the kindof stackers usually found at building materials merchants. If unloadingis done from both sides of the truck, only one stacker with short prongsand one vehicle to drive the stacker are needed. When unloading is donefrom one side, it is necessary either to use long prongs on the stacker,which can drive in under the rear stacks as well, or there must also bea worker on the cargo surface who pulls the rear stacks up to theunloading edge (the driver can also be called upon to perform thistask).

3. Partial stacks or, as in the currently prevailing situation,individual packages can be unloaded, in which case the means used tosecure the loading units and stacks must be undone. When stacks with asurface area of 1.2×1.25 m or 1.2×2.5 m (length of board) are beingunloaded, internal materials handling and storage pose no problems. Allhandling procedures are done with the prongs in the spaces betweenloading units and/or stacks.

The products can be stored in different ways by the building materialsmerchants (FIG. 12). These include storage of entire blocks, providedthe merchant has long prongs at his disposal (this is usually not thepreferred method, however, because of difficulty handling the blocks).Another possibility is storage of units having a smaller surface area,including complete stacks, partial stacks, or individual packages.Subsequent commissioning—after the encircling band has been severed—canbe done as follows (FIG. 13):

1. The upper stack portion is lifted off, secured where appropriate byadditional means such as adhesive tape, and loaded on the buildingmaterials truck; the height (2 m) can be transported on this type ofvehicle. It is possible, then, for 10 packages, for example, to be onthis loading unit.

2. The upper stack portion is lifted off and set down on the ground. Theadhesive tape used to secure it is removed (by pulling off or severing),and taking out packages or putting them back together again poses noproblem.

3. Both handling methods outlined above can also be applied to the lowerstack portion, but if transport by stackers is intended, the entirestack must be set down on top of battens before severing the means bywhich it is secured.

Thereafter, the vehicles to be used for delivery can be loaded with theaid of a forklift (partial stacks in original condition or stacks thathave been put back together again) or, where appropriate, by hand whensmaller quantities are involved (FIG. 14). The units can be unloaded atthe construction site (provided that the appropriate equipment isavailable) with the aid of forklifts, hand pallet trucks, or C-frames ona crane (FIG. 15). However, manual unloading remains an option, in whichcase all means used to secure the loading units must be undone.

All unloading methods can also be used in the case of direct deliverieswhere there is no merchant acting as intermediary.

The advantages of the system according to the invention are summarizedin the following list:

1. Stacker-assisted pre-commissioning at manufacturing site is feasible.

2. Also possible to load smaller units using stacker at manufacturingsite (e.g. loading units with surface area of 1.2×1.25 m), requiringless loading time than manual loading.

3. Stacker loading of units measuring 2.4×2.5 m in original conditionremains an option (short loading times at manufacturing site).

4. Short unloading times at merchant's premises since stackers can beused to do unloading, even ones with short prongs, provided the wrapperis undone (up to 80% less work required).

5. Very short unloading times at merchant's premises, if stacker withlong prongs can be used to carry out the unloading (up to 90% less workrequired).

6. Forklift can be used to dismantle stack, which means it is easy toreach even uppermost bundles during commissioning (once the upper stackshave been set down on the ground).

7. Relatively easy to move partial stacks on through to the constructionsite (by splitting up the unit, e.g. into one 2 m and one 0.8 m unit);possible to make three 2 m units out of two 3 m units to fit thebuilding materials truck.

8. Simplified unloading, even at construction site, when appropriateload-shifting equipment is used, both for deliveries where there is abuilding materials merchant acting as intermediary and for directdeliveries.

9. Simplified handling at the construction site thanks to the ability tograb from below or drive into the loading unit (e.g. by a C-hook on acrane, etc.)

10. Loading unit protected against wear and tear on top and bottom.

11. No load carrier needed for storage purposes (where appropriate,bottom layer to provide protection against moisture).

12. Utilizes no-return component parts that can be re-used by themerchant or on the construction site (wooden laths, EPS battens).

13. No need to return reusable battens or pallet: delivery withoutpallets.

14. Battens do not scoot out of place in cargo space during transport.

FIG. 1:

a) Example of cargo space in a large-capacity truck with loading heightof approximately 3 m (seen from above and side)

FIG. 2:

a) Formation of a stack made of packages from production

b) Front and side view of stack

FIG. 3:

a) The wooden laths in the drawing have approximately 5 mm extra length.

b) A stack held together by an encircling band and adhesive tape.

FIG. 4:

a) There is surface weight exerted on the stack via the wooden laths:the pressure has a force of approximately 200 kg per encircling band(total pressure approximately 400 kg). The tensile force in theencircling band in this case is approximately 1000 N.

b) At the edge of the boards on the side of the stack there are noforces resulting from pressure in a horizontal direction, such as thosefor example when there are angles protecting the edge or when there isno edge protection. High pre-tensioning eliminates horizontal shiftingof the packages against one another, resulting in protection for theboard edges.

c) High pre-tensioning and continuous laths covering the top and bottomalong with continuous foam battens eliminate vertical shifting of thepackages against one another, for example during repositioning of theload, which protects the edges of the boards from damage. Highpre-tensioning creates fixed position for packages within a stack, andit is possible to make a straight outer profile with no protrusions,leading to lower risk of damage caused by bringing partial pressure tobear.

FIG. 5:

a) Size of the foam battens is approximately 100×100×1200.

b) Size of the no-return pallet, made of corrugated cardboard, isapproximately 1200×1250×100.

c) The foam battens are made up of several layers; total height isapproximately 100 mm, e.g. 5×20 mm; 4×25 mm; 2×50 mm (can be re-used atthe construction site).

FIG. 6:

a) A stack, secured by means of a stretch film wrapper or, whereappropriate, boards on top and bottom, or possibly a pallet, thatprevent it from falling apart.

b) Opening that will accommodate 3 or 4 stacker prongs

FIG. 8:

a) Putting together whole blocks without severing the wrapper

b) Putting together stacks

c) Taking apart the stack and putting the stack back together again

d) Putting together individual packages

FIG. 9:

a) Loading entire blocks, whether they are in their original conditionor have been made by putting stacks together

b) Loading of individual stacks

FIG. 10: Example of cargo space on a “jumbo” truck, loading height ofapproximately 3 m

a) Unit in original condition made up of 1.25 m boards

b) Unit in original condition made up of 2.5 m boards

c) Individual stack made up of 1.25 m boards

d) Stack which has been taken apart and put back together again

e) Individual packages

FIG. 11:

a) Unloading of entire blocks, provided special stackers are available(3 long prongs)

b) Unloading of stacks; wrapper, if any, must first be removed; possibleto unload using ordinary stackers (2 short prongs)

c) Unloading of partial stacks

d) Unloading of individual packages, after undoing means used to securethe stack, if any

FIG. 12:

a) Storage of entire blocks (3 long prongs)

b) Storage of stacks (2 short prongs)

c) Storage of partial stacks (ready for commissioning, utilizingmerchant's own additional battens or loading aids)

d) Storage of individual packages

FIG. 13:

a) Cutting through means used to secure stack

b) Lifting off top portion of stack with a forklift and removing thewooden laths

c) Commissioning upper and lower portions of stack

d) Putting together a new unit. If a partial stack is to be pushed alongwhen the loading surface is free, additional means of securing it may beneeded.

FIG. 14:

a) Loading the upper or lower partial stack

b) Loading individual packages

c) Loading re-commissioned stacks (with additional means used to securethem, where appropriate)

d) Example of cargo space on a delivery truck (loading height of 2 to2.5 m)

FIG. 15:

a) Unloading a complete stack using a forklift, hand pallet truck, orC-frame on crane hook; used in direct deliveries

b) Unloading individual packages; all means of securing must be undone

c) Unloading partial stacks using widest variety of methods (forklift,hand pallet truck, C-frame on crane hook, etc.)

List of Reference Symbols

1 Board packages

2 Foam battens

3 Wooden laths

4 Means of securing stack/Encircling band

5 Adhesive tape

6 No-return pallet

7 Wrapper/Stretch film wrapper

8 Additional means of securing

9 Openings for driving in stacker prongs

What is claimed is:
 1. Packing system for a plurality of unit loadsconsisting of plastic foam boards stacked in a plurality of adjacentpiles or piles stacked on top of each other to form a substantiallystable pile consisting of at least two stacked layers of said unitloads, characterized by the fact that spacers are provided between atleast two successive stacked layers so that both stacked layers arevertically disposed and separated by said at least one spacer; at leastone protection device is provided on top of and below the stack toprotect at least partially the external contour of those of said unitloads positioned at the top and bottom of said stacked layers; at leastone fixing device encompassing the outer periphery of the stack so thatit encompasses the stack in such a way that said unit loads in a stackposition are pressed against said unit loads in a directly andvertically adjacent stack position; and the fixing device extends overthe protection device, and wherein the protection device comprises aplurality of multiple, separate, and rectangularly shaped wooden laths,each of said wooden laths separately disposed directly against and alonga single dimension of the top and bottom ones of the stacked unit loads,and not extending beyond the edges of the stacked unit loads.
 2. Packingsystem according to claim 1, characterized by the fact that theprotection device is embodied in an elongated manner and has a lengthextending at least from one side of the top or bottom face of the stackto the other.
 3. Packing system according to claim 1, characterized bythe fact that the fixing device is an encircling band.
 4. Packing systemaccording to claim 1, characterized by the fact that the protectiondevice has an indentation into which the fixing device can be laid. 5.Packing system according to claim 1, characterized by the fact thatthere is at least one adhesive strip affixed to the sides of the unitloads located in the top layer of the stack for the purpose of fixingneighboring unit loads relative to one another.
 6. Packing systemaccording to claim 1, characterized by the fact that the spacers arefour-sided staves.
 7. Packing system according to claim 1, characterizedby the fact that the spacers are foam battens.
 8. Packing systemaccording to claim 1, characterized by the fact that the spacers areno-return pallets with the top and bottom covered by a layer ofcorrugated cardboard and battens made of foam.
 9. Packing systemaccording to claim 1, characterized by the fact that a stack made up ofseveral stacked layers provides, in the lower part of the stack, spacersto create an intermediate space.
 10. Packing system according to claim1, characterized by the fact that at least two stacks can be puttogether to form one larger stack, and can be fixed to each other bymeans of a sort of wrapper that can be put around the sides of thelarger stack.
 11. Packing system according to claim 10, characterized bythe fact that the wrapper is made of stretch film.
 12. Packing systemaccording to claim 1, characterized by the fact that there are at leasttwo fixing devices per stack.
 13. Packing system according to claim 1,characterized by the fact that: the fixing device is an encircling band;the protection device has an indentation into which the fixing devicecan be laid; there is at least one adhesive strip affixed to the sidesof the unit loads located in the top layer of the stack for the purposeof fixing neighboring unit loads relative to one another; the spacersare no-return pallets with the top and bottom covered by a layer ofcorrugated cardboard and battens made of foam; a stack made up ofseveral stacked layers provides, in the lower part of the stack, spacersto create an intermediate space; at least two stacks can be put togetherto form one larger stack, and can be fixed to each other by means of asort of wrapper that can be put around the sides of the larger stack;the wrapper is made of stretch film; and there are at least two fixingdevices per stack.